If you use the internet regularly, chances are you might have come across the "ERR_SSL_VERSION_OR_CIPHER_MISMATCH" error. This error message typically appears on your browser when you try to access a website over an HTTPS connection.

The SSL (Secure Sockets Layer) protocol is used to secure online communication and protect sensitive data transmitted between a web server and browser. However, if there's an issue with the SSL configuration or certificates used by the website, it can result in this error.

Importance of fixing the error

The ERR_SSL_VERSION_OR_CIPHER_MISMATCH error is quite common and can be frustrating for users who need to access important websites or services. Furthermore, ignoring this error and continuing to use the website without resolving the underlying issue can pose a significant security risk.

The SSL/TLS protocol ensures data confidentiality, integrity, and authenticity between two communicating endpoints. If there's an issue with SSL configuration or encryption strength of cipher suites being used by servers or clients, it becomes easier for malicious actors to intercept or manipulate data exchanged during online communication.

Brief overview of the steps to fix the error

If you're experiencing ERR_SSL_VERSION_OR_CIPHER_MISMATCH errors on your browser, don't worry! There are several troubleshooting steps that you can take to resolve these issues quickly.

At a high level, these steps involve checking your browser compatibility with websites' SSL certificate, updating your browser and operating system software if necessary, temporarily disabling antivirus software or firewalls that could interfere with SSL/TLS connections temporarily if any existence found as well as carrying out some more advanced troubleshooting steps if needed. In this article we will go through each step in detail so that you can easily understand what causes this annoying error message and how you can fix errors related to SSL/TLS protocol configuration in your browser or server.

Understanding SSL and Cipher Suites

SSL (Secure Sockets Layer) and its successor, TLS (Transport Layer Security), are cryptographic protocols used to establish a secure connection between a web server and a client. This protocol ensures that all data transmitted between the two parties is encrypted and protected from potential eavesdropping or tampering. The SSL/TLS protocol uses a combination of encryption algorithms, digital certificates, and message authentication codes to ensure the security of the connection.

Cipher suites are sets of encryption algorithms used by SSL/TLS to provide secure communication channels. A cipher suite consists of three main components: key exchange algorithm, bulk encryption algorithm, and message authentication code (MAC) algorithm.

The key exchange algorithm is responsible for securely exchanging keys between the client and server for use in encrypting communication data. The bulk encryption algorithm is responsible for encrypting the actual data being transmitted over the channel while the message authentication code ensures data integrity by verifying that no unauthorized modifications have occurred during transmission.

The Role of Cipher Suites in SSL/TLS Connections

Cipher suites play a vital role in establishing secure connections between web servers and clients using SSL/TLS protocols. When establishing an encrypted connection with a server, both parties must agree on which cipher suite to use based on their capabilities in terms of encryption strength, compatibility with client browsers/operating systems, etc. Since different cipher suites offer varying levels of security against various attack vectors such as brute force attacks or man-in-the-middle attacks, choosing an appropriate cipher suite can significantly impact overall security.

Common Causes of ERR_SSL_VERSION_OR_CIPHER_MISMATCH Error Related to SSL and Cipher Suites

The ERR_SSL_VERSION_OR_CIPHER_MISMATCH error often occurs when there are compatibility issues between the client's browser/operating system capabilities with those supported by the server's SSL/TLS configuration. For example, if a user attempts to access a website that only supports newer cipher suites using an older browser or operating system that lacks support for these cipher suites, an ERR_SSL_VERSION_OR_CIPHER_MISMATCH error may occur.

Similarly, if the server's SSL/TLS configuration is not up-to-date and does not support modern cipher suites, clients attempting to connect using such ciphers may also encounter this error. Other causes may include misconfigured or expired SSL certificates and issues with intermediate certificates used for certificate chain verification.

Troubleshooting Steps

Step 1: Check browser compatibility with website's SSL certificate

One of the most common causes of the ERR_SSL_VERSION_OR_CIPHER_MISMATCH error is a mismatch between the SSL/TLS protocol used by the website and that supported by your web browser. This can occur when the website uses an outdated or weak cipher suite that is not supported by your browser.

To check if this is the case, you need to check your browser's compatibility with the website's SSL certificate. To do this, start by examining the SSL certificate details of the website by clicking on the lock icon in your web browser's address bar.

Look for any warnings or errors related to SSL/TLS encryption and take note of any mentioned cipher suites. Then, cross-check these cipher suites with those supported by your web browser to see if they match up.

Step 2: Update Browser and Operating System

Another common cause of ERR_SSL_VERSION_OR_CIPHER_MISMATCH error is outdated software on your computer or device. Outdated browsers, operating systems, drivers, and system files can prevent proper communication with websites using modern encryption protocols such as TLS 1.2 or higher. To avoid this issue, try updating both your web browser and operating system to their latest versions.

This will ensure that you have all necessary updates installed to support modern encryption standards. Additionally, make sure any extensions or plugins in your web browser are updated as well.

Step 3: Disable Antivirus or Firewall Temporarily

In some cases, antivirus software or firewalls can interfere with SSL/TLS connections on certain websites leading to ERR_SSL_VERSION_OR_CIPHER_MISMATCH error. These security programs may block access to certain ports used by TLS/SSL or inspect SSL traffic, which can cause a mismatch between SSL/TLS versions between the browser and website. One way to fix this issue is to temporarily disable your antivirus or firewall software and then try accessing the website again.

Step 4: Clear SSL State and Cache

One of the reasons why ERR_SSL_VERSION_OR_CIPHER_MISMATCH could persist after trying the basic troubleshooting steps is due to cached SSL certificates. By clearing cached data, it would force the browser to get a fresh copy of the certificate which may fix the problem.

To clear SSL state and cache on Google Chrome, follow these steps −

  • Click on the three dots at the top right corner of your browser window.

  • Select "Settings".

  • Scroll down and click on "Advanced".

  • Select "Privacy and security".

  • Select "Clear browsing data".

  • Select "Cookies and other site data" and "Cached images and files" options.

  • Pick a time range that suits you best.

  • Click on “Clear data”

Step 5: Check Server-Side Issues

If you’ve ruled out client-side factors as causes of ERR_SSL_VERSION_OR_CIPHER_MISMATCH, it’s possible that there are server-side issues causing this error. The following are some server-related issues that might cause this error −

  • The website is no longer using SSL/TLS protocol

  • The website doesn’t have an appropriate TLS/SSL Certificate installed or their certificate has expired.

In these cases, you should contact your hosting provider or system administrator to check whether they can fix any server-side issues.


The ERR_SSL_VERSION_OR_CIPHER_MISMATCH error can be a frustrating error message for any web user. However, as outlined in this article, there are several troubleshooting steps you can take to eliminate this issue and regain access to the websites you need. By ensuring that your browser supports modern encryption standards, updating your software regularly, and temporarily disabling security programs when necessary, you can prevent this error from occurring in the future.

Updated on: 05-Jun-2023


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